Gis C# Form 做一個ComboBox，只需要傳Ilayer給它，即可顯示該圖層所有字段

myFieldComboBox1.Layer = f1;

using ESRI.ArcGIS.Carto;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace MyGIS.Model
{
    public class MyFieldComboBox : System.Windows.Forms.ComboBox
    {
        List<string> fields = new List<string>();
        ILayer layer = null;
        public ILayer Layer
        {
            get
            {
                return layer;
            }
            set
            {
                //////return;
                layer = value;
                if (layer == null) return;
                IFeatureLayer fl = layer as IFeatureLayer;
                if (fl == null) return;if (fl.FeatureClass == null) return;
                fields = new List<string>();
                for (int a = 0; a < fl.FeatureClass.Fields.FieldCount; a++)
                {
                    fields.Add(fl.FeatureClass.Fields.Field[a].Name);
                }
                DataSource = null;
                DataSource = fields;
                if (fields.Contains("name"))
                    this.SelectedItem = "name";
            }
        }

        private void InitializeComponent()
        {
            this.SuspendLayout();
            // 
            // MyFieldComboBox
            // 
            this.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
            this.ResumeLayout(false);

        }
    }
}